Leaflet kinematics after the Yacoub and Florida-sleeve operations: results of an in vitro study.

Abstract

The Florida-sleeve is a valve-sparing technique that causes minimal interference to leaflet kinematics and aortic root dynamism. The aim of this in vitro study was to evaluate the effects of the Florida-sleeve and Yacoub techniques on aortic leaflet kinematics. Two groups of 6 whole porcine hearts were treated with either the Florida-sleeve technique or the Yacoub technique and tested in a pulsatile loop. Valve fluid dynamics, coronary flow analysis and valve echocardiograms were performed both before and after the procedures. Both procedures showed no difference in rapid valve opening time as compared with their respective baseline values. The Florida-sleeve procedure showed a shorter slow closing time (192 ± 19 ms vs baseline 244 ± 14 ms, P = 0.016) and increased slow closing velocity (-1.5 ± 0.4 cm/s vs baseline -0.8 ± 0.4 cm/s, P = 0.038). In the rapid valve closing phase, the Yacoub procedure showed a trend towards slower closing valve velocity (-16 ± 9 cm/s vs baseline -25 ± 9 cm/s, P = 0.07). The Yacoub procedure showed larger leaflet displacement at the end of the slow valve closing time that was 2.0 ± 0.5 cm vs baseline 1.5 ± 0.3 cm, P = 0.044. When comparing the Florida-sleeve and Yacoub procedures, the former showed statistically significant shorter slow valve closing time (P = 0.017). This study showed that the Florida-sleeve technique alters the slow closing phase of the aortic valve leaflet kinematics when compared with both the normal baseline and Yacoub procedure, while the latter showed a larger leaflet displacement before the rapid closing valve phase.